2021 journal article
Genomic Breeding for Diameter Growth and Tolerance to Leptocybe Gall Wasp and Botryosphaeria/Teratosphaeria Fungal Disease Complex in Eucalyptus grandis
FRONTIERS IN PLANT SCIENCE, 12.
Eucalyptus grandisis one of the most important species for hardwood plantation forestry around the world. At present, its commercial deployment is in decline because of pests and pathogens such asLeptocybe invasagall wasp (Lepto), and often co-occurring fungal stem diseases such asBotryosphaeria dothideaandTeratosphaeria zuluensis(BotryoTera). This study analyzedLepto,BotryoTera, and stem diameter growth in anE. grandismulti-environmental, genetic trial. The study was established in three subtropical environments. Diameter growth andBotryoTeraincidence scores were assessed on 3,334 trees, andLeptoincidence was assessed on 4,463 trees from 95 half-sib families. Using theEucalyptusEUChip60K SNP chip, a subset of 964 trees from 93 half-sib families were genotyped with 14,347 informative SNP markers. We employed single-step genomic BLUP (ssGBLUP) to estimate genetic parameters in the genetic trial. Diameter andLeptotolerance showed a positive genetic correlation (0.78), whileBotryoTeratolerance had a negative genetic correlation with diameter growth (−0.38). The expected genetic gains for diameter growth andLeptoandBotryoTeratolerance were 12.4, 10, and −3.4%, respectively. We propose a genomic selection breeding strategy forE. grandisthat addresses some of the present population structure problems.